My bad! "Terrec" posted on the Discord the key info that this started happening once a bunny was dead. Turns out the plugin that does the "bust" images on the sides of the screen was being turned off when you talk to a dead bunny in the house, and not turned on again after that.
Made a bugfix file, which you can unZIP in the www\data folder, but I can't post it here. Check my own itch.io page (yes I'm also BishoujoHelper, long story...) in a few minutes. Or the BunnyHunter Discord #hunter-bug-reports channel.
But I will also send DO! this same file, and let him put out another full download if you're worried about security/trust.